Invasive mussel discovery in Idaho puts Pacific Northwest on alert

The DNA lab results came back Monday.

“The initial phone call was a bit of a shock,” said Nic Zurfluh, the Idaho State Department of Agriculture bureau chief for invasive species. “But this is what we plan for.”

The call confirmed that routine water sampling had captured the larval form of the quagga mussel – only visible under a microscope – freely floating in the Snake River by Twin Falls.

The species is one of the most invasive in the U.S., and its invasion into the Pacific Northwest has long been dreaded.

By Tuesday, the popular waterfront park in the Snake River Canyon was shut down and nearby lakes and river access points were closed to recreationists with boats, kayaks, paddle boards and canoes. Idaho Gov. Brad Little called two press conferences.

“The what if – what if it's unconstrained – is going to leave a huge mark on this valley and the state of Idaho for a long, long time,” Little said in Twin Falls.